Malignant peripheral nerve sheath tumor (MPNST) is an exceedingly rare and aggressive tumor, with limited literature on its management. Herein, we present our series of surgically managed craniospinal MPNSTs, analyze their outcomes, and review the literature.

We retrospectively reviewed surgically managed primary craniospinal MPNSTs treated at our institution between January 2005 and May 2023. Patient demographics, tumor features, and treatment outcomes were assessed. Neurological function was quantified using the Frankel grade and Karnofsky performance scores. Descriptive statistics, rank-sum tests, and Kaplan-Meier survival analyses were performed.

Eight patients satisfied the inclusion criteria (4 male, 4 female). The median age at presentation was 38 years (range 15-67). Most tumors were localized to the spine (75%), and 3 patients had neurofibromatosis type 1. The most common presenting symptoms were paresthesia (50%) and visual changes (13%). The median tumor size was 3 cm, and most tumors were oval-shaped (50%) with well-defined borders (75%). Six tumors were high grade (75%), and gross total resection was achieved in 5 patients, with subtotal resection in the remaining 3 patients. Postoperative radiotherapy and chemotherapy were performed in 6 (75%) and 4 (50%) cases, respectively. Local recurrence occurred in 5 (63%) cases, and distant metastases occurred in 2 (25%). The median overall survival was 26.7 months. Five (63%) patients died due to recurrence.

Primary craniospinal MPNSTs are rare and have an aggressive clinical course. Early diagnosis and treatment are essential for managing these tumors. In this single-center study with a small cohort, maximal resection, low-grade pathology, young age (< 30), and adjuvant radiotherapy were associated with improved survival.

A 65-year-old female patient has a history of malignant triton tumour of the right upper lobe of the lung. She underwent right upper lobectomy and lymphadenectomy in May 2018. She presented in November 2019 with pathological fracture of the left proximal femur. It was not associated with neurofibromatosis. We decided to do an excisional biopsy of the mass and proximal femoral replacement followed by radiotherapy. Four months later, she presented with local recurrence. We organised a multidisciplinary team between the orthopaedic, histopathology and oncology teams. Then, we decided to treat her with chemotherapy. After 2 months of follow-up, she responded well to the chemotherapy with no further deterioration of her condition.

Malignant triton tumor (MTT) is a malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. The prognosis of patients is poor, and due to its rarity, large case studies are lacking. The aim of this study is to describe the clinical features and identify potential prognostic factors. Two patients with MTT in the head and neck treated at our department are reported. A literature search revealed another 198 published cases. All of these cases then went through a retrospective analysis. The ratio of male-to-female incidence was 1.5:1, and the median age at diagnosis was 29 years. In 41.7% of cases it occurred in patients with neurofibromatosis type 1. The five-year survival of MTT was found to be just 35%. Cox proportional hazards analysis revealed that complete resection (hazard ratio, 0.396; P=0.032) and metastases (hazard ratio, 3.188; P=0.004) were associated with mortality, indicating that complete resection may lead to a longer life span, and that the existence of metastasis suggested a worse prognosis for patients with MTT.

Malignant triton tumor (MTT) is a highly aggressive malignant neoplasm, classified as a variant of malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. MTT is rarely reported in children, and its true prevalence may be underestimated. We herein report such a case in an 8-year-old boy who presented with a mass over the trapezius muscle. He was previously diagnosed with neurofibromatosis in the same area. Four years later, a follow-up magnetic resonance imaging revealed an intradural tumor recurrence at the level of C1-C7. An immunohistochemical test result was positive for S-100 protein and desmin, which confirmed the diagnosis. The patient outcome was fatal despite multimodal therapy. The possibility of this rare but devastating tumor must always be considered when patients present with new compressive spinal symptoms.

Malignant triton tumor (MTT) is defined as malignant peripheral nerve sheath tumor with rhabdomyoblastic differentiation. Intracranial MTT is extremely rare, and only four cases have been reported in the literature. Here, we report a case of MTT occurring in the cerebellopontine angle, and describe its histopathological characteristics, immunohistochemical features, and prognosis.

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